docs: def aliases(self, indices=None):
          """
          Retrieve the aliases of one or more indices.
          ( See :ref:`es-guide-reference-api-admin-indices-aliases`)
  
          :keyword indices: an index or a list of indices
  
          """
          path = self.conn._make_path(indices, (), '_aliases')
          return self.conn._send_request('GET', path)